Fix single item query return type (dropbox#199)

Co-authored-by: Ivan Levkivskyi <[email protected]>

sqlalchemy-stubs/orm/session.pyi

@@ -1,4 +1,4 @@
-from typing import Any, Optional, Type, TypeVar, Union, overload
+from typing import Any, Optional, Tuple, Type, TypeVar, overload
 
 from sqlalchemy import Column
 from sqlalchemy.orm.query import Query
@@ -66,9 +66,11 @@ class Session(_SessionClassMethods):
     def bind_table(self, table, bind): ...
     def get_bind(self, mapper: Optional[Any] = ..., clause: Optional[Any] = ...): ...
     @overload
-    def query(self, entity: Union[Type[_T], Column[_T]], **kwargs) -> Query[_T]: ...
+    def query(self, entity: Type[_T], **kwargs) -> Query[_T]: ...
     @overload
-    def query(self, *entities, **kwargs) -> Query: ...
+    def query(self, entity: Column[_T], **kwargs) -> Query[Tuple[_T]]: ...
+    @overload
+    def query(self, *entities, **kwargs) -> Query[Any]: ...  # plugin is needed for precise type
     @property
     def no_autoflush(self): ...
     def refresh(self, instance, attribute_names: Optional[Any] = ..., lockmode: Optional[Any] = ...): ...